


Side-Dick Adrien

by CrypticCravings (Sekaiinokoi)



Category: Miraculous Ladybug
Genre: Adrinette, Cheating, Crack, F/M, Marichat, Marinette cheats on Cat Noir with Adrien, No outright descriptions of sex, Rated T for Mild Language, Side-Dick Adrien, This started out as a joke!, adrienette - Freeform, please don't take any of this seriously
Language: English
Status: Completed
Published: 2017-06-01
Updated: 2017-06-01
Packaged: 2018-11-07 14:30:17
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,301
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11060934
Author URL: https://archiveofourown.org/users/Sekaiinokoi/pseuds/CrypticCravings
Summary: Marinette is cheating on Cat Noir. What happens next will blow your mind!!





	Side-Dick Adrien

**Author's Note:**

> HAPPY BIRTHDAY SARAH!!  
> This fic is a gift to my lovely little on her 21st birthday!  
> Back in February, I was scrolling through the Sidekick Adrien AU tag on Geek-Fashionista/PrincessKitty's Tumblr, because let's be real that AU is a gift, when ThisAwkwardBitch looked over my shoulder and asked "Does that say Side-Dick Adrien???"  
> Thus, this idea was borne!! Enjoy this nonsense that started out as an inside joke and spiraled out of control!

Marinette knew she was a piece of shit.

She didn't like to admit it, but she knew it was true. She was cheating on the love of her life with the other love of her life, stringing along one while fooling around with the other.

But who could blame her? How could she be expected to remain faithful to a man whose face she had never seen?

She had never been a liar. In fact she hated liars with a passion, which was giving her some serious issues with herself. If her middle school self could see her now, she'd probably smash her face in with her yoyo.

Marinette groaned and considered locking her window, but she couldn’t bring herself to do it.

The visits had started up about a month after she'd moved out on her own for university. Cat Noir would swing by her place late at night, after patrols had ended, and Marinette had let him in.

Not for any kind of ulterior motives, or anything! Of course not!

Just for some milk and cookies, and small talk.

Then it progressed to some snuggling.

And kissing.

And then….

At first it had just been nice to talk to her partner outside of the mask. He'd always been soft hearted, but seeing him in her living room, snuggled up in a fluffy blanket with one of her pink mugs in his hands, his leather cat ears smoothed back in contentment and his eyes shimmering in the dull light… it made her heart race in a way she had never felt before.

Soon she was feeling it whenever he was near. It didn’t matter if he was battling an akuma like they did so often, patrolling together, or  if he was tapping on her window at midnight. The sight of him made her fill with warmth.

Then one night, when they had been laughing at a stupid comedy on late night television, things between them had grown heated.

After three more instances, she knew they had to talk about it.

It wasn't like she'd wanted it to stop. Sleeping with Cat Noir was an exhilarating experience. She just wanted to know where they stood. Did he still have feelings for Ladybug? Why did he keep coming to her? What exactly was their relationship now.

Two years later, and he'd still only answered one of her questions. Cat Noir assured her that while he still had love for Ladybug, his romantic feelings for her had faded.

It was like a double edged sword for Marinette. He'd rejected one side of her in favor of being with her other half just when she was ready to accept him with her whole self. For now, she'd have to be happy with the way things were.

Since then,  though they'd never formally defined their relationship, Marinette considered him her boyfriend. She could feel that he thought of her in much the same way. She was happy with him just the way things were, and he was happy with her. She thought she had all she ever needed.

Until that fateful day at university.

Marinette shoved her face into a pillow and reminded herself once again that she was an absolute piece of shit.

She thought that she had gotten over Adrien years ago; thought that her feelings for him had faded into a high school memory. Unfortunately, she had no way of knowing how wrong she was.

They went to the same university, her for design and him for fashion marketing--he was still working under his father, after all. They had a few of the same classes where their general requirements overlapped, and after a particularly stressful exam, Adrien asked her to get a drink to decompress. She'd accepted without a second thought.

So they'd sat together in the dim light of the bar. Two drinks in, and Marinette had been far from being even remotely drunk, but she was decidedly more comfortable than she had been even an hour before. She and Adrien talked about their classes, laughed and joked, and she wondered why they hadn't spent more time together before. It wasn't like she was still hung up on her middle school crush. She was with Cat Noir. And she was totally, 100% over Adrien.

She thought she was, at least. Until he looked at her with his luminescent green eyes, warm under the dim light of the bar. The look in Adrien's eyes reminded her so much of the way her cat looked at her that she momentarily lost herself. It was like he was there with her instead of Adrien.

She almost thought he leaned into her, that he wanted to kiss her.

And before she knew it, she was kissing him. She was leaning into him.

She wanted to blame the alcohol, but she knew she hadn't had nearly enough for her to lose her sense that much.

For whatever reason, that night she hadn't gone home to her apartment. Maybe it was her leftover feelings for Adrien. Maybe it was her projecting her love for Cat Noir onto Adrien. Maybe she was just feeling lonely, and he was convenient, she didn't know. But that one night had been a mistake she couldn't take back. Sometimes, she wondered if she even wanted to.

The only thing Marinette could be sure of was that she was a piece of shit for being with Adrien that night, and every night she had been with him in the months since, because after that first night, he kept calling. For some reason, whenever he called, she just couldn't say no to him, or those green eyes.

"Tiki, I have a problem," Marinette complained.

"You have several problems," her Kwami quipped. "Are you going to lock the window tonight or not?"

Marinette glanced at the window one more time. She knew she should lock it. It was the right thing to do. She couldn't keep inviting Cat Noir in if she was going to keep messing around with Adrien. But on the other hand, she couldn't bear to lock him out if he came. It was rare to see him lately, and she wasn't going to deprive herself of the opportunity to snuggle with her boyfriend if he wanted to stop by.

Instead of locking the window, she decided she would just go to bed. If he stopped by, he would stop by. He knew he was welcome to come in even if she was already asleep.

 

* * *

 

Adrien knew he was a piece of shit.

He admitted it freely, and without hesitation. He was a garbage person, and he wasn't afraid to say it. He wasn't even high quality garbage, like the kind that you might consider recycling.  He was 100%, honest to goodness trash, because he had tricked  his girlfriend into cheating on him with himself.

When it had first happened, he almost wanted to be mad at Marinette. He knew that wouldn't be fair of him, though. After all, he had practically lured her into it. He'd initiated the whole thing thanks to his fucked up, over active libido. Looking at her dark blue eyes in the dim light of the bar, the way she smiled and laughed at his dumb jokes, her delicate fingers tucking her soft hair behind her ear, her every movement drew him in until he had forgotten where--and who--he was. For a moment, he forgot that he was actually Adrien, and not Cat Noir, and that she didn’t know that she was sharing a drink with her actual boyfriend instead of her classmate. So, with the warmth of a couple of drinks and the boldness inspired by the romantic lighting, he'd been the one to lean in first.  
Then the next time it had happened, against his better judgment, he'd been the one to ask her to study together. Unable to help himself, yet again, they'd ended up in bed together. From there, it just kept happening. Whenever he was around her, either as Cat Noir or Adrien Agreste, he couldn't help it. He felt so free when he was with her. He was at his happiest when he was in her company, and all rationale flew out the window. When he was with her, he wanted to show her how happy she made him.

In all of the confusion the last few months, only one thing was certain--somehow, he had to stop stringing Marinette along, either as Adrien, Cat Noir, or both.

"What do I do, Plagg," Adrien groaned, turning over again to glare up at his high ceiling. "I should tell Marinette the truth, right?"

Plagg clattered about in the trash bin for a moment before lazily floating over to Adrien's spot on the floor. "Which truth are you talking about, kid? The part where you lured her out to the bar to seduce her, or the part where you're actually Cat Noir, or the part where you've been abusing your superhero powers to get close to her for almost three years now?"

Adrien turned his head away from Plagg indignantly--and noticed off hand that he should probably clean all of the dust from under his bed--before responding. "I don't know. All of the above, I guess? Every time I think about it, the guilt is killing me, but I can't just out myself to her. Telling her that I'm Cat Noir might put her in Danger. Not to mention, Ladybug would be pissed if I revealed myself to a civilian, especially without talking to her about it first. And can you imagine what would happen if Ladybug knew I was sneaking around like this? She probably already thinks I'm some kind of playboy. If she knew how I was messing around with Marinette--"

"Aagh! This whining is killing me," Plagg finally shouted. He zipped up to Adrien and got right in his face, "You need to figure out what you're going to do about this. I've been listening to your love problems for seven years now, and it's giving me indigestion."

"Plagg, this is serious!"

"It's always serious. Figure it out, or I'll take care of things for you!"

With that, Plagg gave a frustrated huff and flew off to the mini fridge Adrien had installed years back for Plagg's cheese obsession.

"You suck so much, you dumb Kwami," Adrien muttered.

A cheese container flew across the room and smacked him in the head.

"Ouch!!"

 

* * *

 

The next day, Adrien's forehead was still sore. After the first cheese lid, Plagg decided to launch every container of sheese he had at Adrien. He figured it was to show just how displeased the Kwami was with what Adrien was doing. He was surprised there wasn't a visible bruise.

He sighed as he pulled his laptop out of his bag for the lecture. He had to stop thinking about--

"Hey, Adrien."

_Marinette._

A huge smile involuntarily spread across his face as she approached her seat next to him.

"Morning, Mari." He felt Plagg roll about in his pocket, probably already displeased with the interaction.

They didn't speak any more than that during class, both of them emotionally exhausted from the night before of lamenting their love lives.

But no amount of rational thought, emotional exhaustion, or Plagg nudging him was enough to stop Adrien when he saw Marinette's smile at the end of class. She looked tired, and all he wanted to do was cheer her up. So he did something he knew he shouldn't and asked her to meet him for dinner.

"Nothing fancy," he said, "just some takeout? We can work on that paper."

Marinette knew she should say no. Going to Adrien's apartment and having dinner together was dangerous. So so dangerous. She had already been betraying her masked boyfriend for a few months, and she felt herself sinking further and further every time she looked into Adrien's impossibly green eyes. It wasn't fair to either of them. It wasn't fair to Cat Noir. He trusted her. Even though he never said it outright, he loved her. And she loved him. It wasn't fair to Adrien, either. He had no idea that she was actually dating a super hero--no one did. It wasn't fair of her to treat Adrien like her side dick while leading him on the way she was. But it wasn't like Adrien was trying to be her main, or anything. Their relationship was always physical, after all. No emotions. He never tried to date her. He never gave any bold confession of love. It was just sex. Maybe that was why Marinette felt she could justify sleeping with him. Was it really cheating if it was just physical?

If Tiki could hear her thoughts, she would have slapped Marinette. As it was, Marinette wanted to slam her head into the wall repeatedly, shouting "Stupid, stupid, stupid, stupid, stupid" until she gave herself a concussion. It was wrong. Being with Adrien was wrong. Having dinner with him was wrong. Studying with him was wrong. Wrong, wrong, wrong, wrong wrong.

She needed to turn him down, and put an end to this nonsense immediately.

"Sure," Marinette said with a grin. "Is Indian food alright?"

_Stupid! Wrong and stupid! Wrong, wrong, wrong, stupid, wrong._

Could she do nothing right??

 

* * *

 

Marinette walked back to her apartment from Adrien's feeling dirty and low, but also satisfied and content. She hated herself for it, a feeling that was becoming more and more common every time they met up. Maybe it was time for her to cut Adrien loose. She couldn't keep doing this to Cat Noir.

"Well well well, look what I found."

Speak of the devil…

Marinette peered up at the street lamp ahead to see her boyfriend/Cat-themed hero of Paris perched on the light, grinning down at her. Despite herself, she felt the tension in her shoulders ease. The sight of her partner always did that to her. He made her feel safe, even from her own worries.

"Look what the cat dragged in," She said, putting a hand on her hip.

His grin grew and he lept off of the light, landing deftly before her. "Isn't punning my job, Princess?" He took her hand and placed a kiss on her knuckles.

"What can I say, you're rubbing off on me." Marinette took the opportunity to scratch his head right behind the leather of his ears. "What brings you out here at this time of night? Looking for damsels to rescue?"

"As a matter of fact, I am," he teased back, sweeping an arm over her shoulders. "And look how lucky I am to have found a beautiful princess, wandering about the streets of Paris without a knight to accompany her. May I have the honor of escorting you home, fair lady?"

Marinette mentally kicked herself for being so flustered by his offer. She should not be getting this giddy running into her boyfriend as she walked home from her side piece's apartment, but she was. For just a moment, Marinette shoved her guilt aside. Adrien wasn't there right then, her boyfriend was. She only saw him so rarely, and she was determined to enjoy herself. "Of course! Oh, what would I have done if you hadn't come along, my fair, brave knight?"

"Well then, Princess," Cat Noir literally swept her off her feet, lifting her into a princess carry in his arms, "hold on tight. I'll be sure to deliver you safely to your castle."

Marinette wrapped her arms around her kitten's neck and kissed him on the cheek. "Thank you."

He averted his eyes, but she saw his cheeks growing pink. "Hold on."

So she did, and he jumped over buildings and streets to bring her back to her apartment.

 

* * *

 

It was time to come clean. After his latest fuck up, sleeping with Marinette as Adrien _yet again,_ he had come to the conclusion that he was completely hopeless. He needed to confess to Marinette that he was Adrien and Cat Noir. It was only fair. Besides, once he came clean, they could be together for real. He could tell her he loved her, and stop sneaking into her window at midnight. They could date openly rather than rely on poorly veiled booty calls masked as "study" dates.

But before he did that, he wanted to tell Ladybug first. After all, they were partners. Even though he had long moved on, she was his first love. He trusted her with his life, and she trusted him. If he was going to reveal himself to anyone, he had to do so to Ladybug first.

He would talk to her on patrol.

 

* * *

 

"You want to what?"

Cat Noir winced, but quickly realized that Ladybug didn't sound _mad_ like he had expected. Maybe this was good.

"There's this girl I've been seeing," he said, conveniently leaving out the fact that he'd been "seeing" her as Cat Noir rather than his civilian self. "We've been seeing each other for a few years now, and I…I want to be honest with her. About everything. I want to really be with her, and I can't do that with a secret this big. I know it might be dangerous, but I'm prepared to protect her. I'll take full responsibility for her safety, and anything that happens as a result of her knowing about…well, this. But I know I can trust her." Adrien sighed, hoping his explanation was enough.

Ladybug was quiet for a moment. She hoped he couldn't see the flush on her cheeks. That was the closest to a love confession she'd ever gotten from Cat Noir. He wanted to be serious about her, and she was fooling around with Adrien on the side. _Stupid, stupid, stupid_. But if he trusted her with his identity, cared about her enough to reveal his true identity to her, she would never be with Adrien again. She would be with him, and she would give her whole heart to him.

"Okay," Ladybug nodded, "you have my blessing."

Cat Noir's smile was brighter than the lights on the Eiffel Tower. He punched his fist in the air, gave a whoop of victory, then lifted Ladybug off of her feet and swung her in a circle. "Thanks, LB! You have no idea what this means to me." He put her back on the ground. "But before I run off to see my princess, there's something I have to do first."

Ladybug tilted her head to the side. What more could he possibly want?

"I want you to be the first person I tell, LB. You're my partner, and it doesn't feel right to tell a girl I'm seeing before I tell you."

If Ladybug thought her heart was pounding hard before, it had nothing on this. He wanted to tell Ladybug first. If that was the case, Marinette reasoned, maybe it was time for him to know who Ladybug was as well. After all, it was only fair. Ladybug stifled a giggle. She couldn't wait to see the look on his face when she showed him that Ladybug was actually his Princess. 'Surprise,' she would say, 'it was me all along!'

Then, everything would be out on the table.

Well.

Almost everything.

Ladybug nodded. "S-sure. That's…Yeah. Th-that's good." Curse her nervous stutter!

Cat Noir smiled at her one more time and took a step back on the roof, so that she could see him fully.

This was it.

"Plagg, de-transform me," Cat Noir said, feeling his transformation release around him.

Ladybug blinked for a moment, not fully processing what she was seeing. She shook her head, hoping to dispel whatever illusion was standing in front of her, but it didn't go away.

Adrien Agreste stood before her, rubbing the back of his neck sheepishly before holding his hand out for her. "Nice to meet you, my lady. I'm Adrien."

Ladybug scrunched her whole face up in displeasure as the shocking reveal continued to register. Ladybug's fist balled up in fury.

"You are Such An ASSHOLE!" Ladybug's voice climbed in volume with every word, startling Adrien out of his skin.

Ladybug lunged at him furiously and smacked him in the arm.

"Ow! Ladybug, what the hell?!" He held up his hands in a feeble attempt to defend himself.

"I can't believe you, you mangy cat!" She emphasized each word with a smack on his arm, his shoulder, his head, anywhere she could reach him, making him cringe away from her.

"Ladybug, what's your problem?!"

"My problem is you, you mangy, philandering, asshole tom cat! How could you do that to me?"

"Ouch! Do what? You're not making any sense!"

Ladybug finally pulled back from her assault--Adrien knew he would have bruises later. Her bottom lip jutted out and quivered, but instead of the former fury that had filled her eyes, they were filled with pain and tears.

"Tiki, spots off," she murmured.

A bright light engulfed ladybug, surrounding her with a pink halo until Ladybug was no longer standing before him. In her place stood Marinette Dupain-Cheng, Cat Noir's girlfriend, and Adrien's lover.

Adrien's brain suddenly shorted out. Of course, the plan had been to reveal himself all along, but he had never expected it to go like this.

He could hear Plagg stifling his laughter behind them, but couldn't bring himself to say anything to the pest. He stared, instead, into the giant blue eyes before him; the same blue bell eyes that he had fallen for seven years ago and thought to be out of his reach were the same midnight blue eyes he had been gazing lovingly into for the past three years. Those beautiful eyes that so often soothed his soul were filled with tears over his betrayal.

"Marinette," Adrien reached for her, "I am so so--"

Before he could even get the words out, Marinette opened her mouth and let out a deafening wail that could rival any alley cat's midnight howls.  Before Adrien could react, she launched herself at him, tears falling as she sobbed against him.

"A-Adri-en, C-Cat,' she hiccupped, clinging to him and gasping between sobs, "I am s-so so-r-ry. I am horrible. I've w-wanted to t-tell you for months, but I was so a-afraid of l-loosing you--of-of losing b-both of you. I was s-selfish, and a liar, and I'm..I am sorry for ch-cheating on you, kitty."

Adrien had never expected this out of her. He had been so focused on the weight of his own deception, he hadn't even considered the effect the guilt would have on kind hearted Marinette. "Mari…"

"Adrien, you should dump me. Just leave me right now. I don't deserve you. You need to be with someone who won't lie to you." On anyone else, the words would have seemed like self pity, but when Marinette spoke them, he could tell that she genuinely believed them. She truly and honestly believed she didn't deserve to be with him.

"Marinette, I'm not going to break up with you."

She pushed him away, turning away from him. "I betrayed your trust, _chaton_. I went behind your back with someone else. It doesn't matter that the other man was still you. I wasn't faithful."

Adrien put his hands on Marinette's shoulders and turned her around, "Marinette, I never even considered what we were doing cheating." He wiped the tears from under her eyes.

She grimaced. "That's stupid. Of course it was cheating. I didn't know you were…well, you."

Adrien couldn't help but laugh. "I didn't consider it cheating because it was me the whole time. I'm so sorry I made you feel like you were being unfaithful. I wasn't thinking about that at all, and I put you through so much. I'm so sorry, Mari. Can you ever forgive me?"

Marinette sniffled. She wrapped her arms around his chest and buried her face into it. "If you're alright with a cheating liar like me, there's nothing to forgive."

Adrien rubbed soothing circles on her back and grinned. "It's okay, Marinette. I don't mind being your side dick."

She feebly smacked his shoulder blade, triggering a chuckle out of him. "Stupid Cat."

Adrien pressed a kiss to the top of her head, relieved that everything was finally out in front of them. "I love you, Bugaboo."

Marinette tensed in his arms, and Adrien realized that in their three years together he had never said those words to her, in or out of the mask. For a second, he worried she didn't return his feelings. Maybe she was just after a physical relationship after all. Maybe he had just projected his feelings onto her. After all, their relationship was mostly physical, both with Cat Noir and Adrien. Maybe he'd overstepped after all--

Marinette's hold on him tightened further. "I love you too, _mon minou_."

He breathed out a sigh of relief, and said the words once again. "I love you, too, Marinette."

Marinette finally lifted her head, eyes still puffy from crying. "I love you, too, Adrien."

They could both practically hear their kwami cheering over their stupidity a few feet away as they kissed.

"Never in my life have I been stuck with a more stupid Chosen," Plagg lamented, watching the two of them make out on the roof top.

"Oh calm down," Tiki chided him. "They were meant to be together, with or without the mask. It was inevitable that there would be misunderstandings."

Plagg made a face, sticking out his tongue, and held his tiny paw out towards the couple. "They're both just…so stupid."

Tiki chuckled. "At least they're happy."

And they were. Adrien and Marinette lived the rest of their lives together, stupidly happy and in love.

**Author's Note:**

> This didn't end up being as much crack as I expected, but still.  
> ((I can't believe I wrote this with my own two hands.))


End file.
